# Search results

I am interested in learning more about Klein's paradox. My QM book said you need QFT to treat it properly. I did a quick internet search but found no expository materials. Even Wikipedia had no mention. This forum had very little of substance that I could find on the subject. Maybe someone can...
2. ### SL(2,C) etc

Thanks James - I really appreciate your effort. I will read through your answer carefully. I posted a similar question under linear algebra but didn't get a serious answer. What prompted this was the fact that 1 0 0 1 0 1 -1 0 work like complex numbers so I wondered what the whole...
3. ### What is this ring called?

repeat after me ... "I don't know" ... all together now ... "I don't know"....
4. ### What is this ring called?

NateTG, 0 is just 0 0 0 0 and + is just matrix addition and x is just matrix multiplication. I found some stupid wikipedia thing where these 4 were given names like K0 K1 K2 K3 but no references were given so that was a dead end. I'm at work so I can't look it up in my books.
5. ### What is this ring called?

Thanks, NateTG, for taking the time to respond. That is what I thought until I realized that it had to be a RING for closure. So then I thought I would like to know the NAME of it, at least.
6. ### What is this ring called?

This set of four matrices: 1 0 | 0 1 | -1 0 | 0 1 0 1 | 1 0 | 0 1 | -1 0 are closed under multiplication. What is it called? I know that it is not those silly quaternions
7. ### SL(2,C) etc

When people discuss the Lorentz transformation, the start talking about "groups " of transformations SL(2,C), SO(1,3) etc. Looks impressive! Where can I learn this stuff too? I asked a similar question in the Linear Algebra section but it gets less traffic
8. ### Boundary Conditions for Fermi Gas

Hi I am new to solid state. I just read about fermi gas in a cube. For some reason the author used periodic boundary conditions? Why didn't they choose finite well potential where the height of the well is related to the work function?

Thanks, Creator - I will definitely check that out! I appreciate your help!:smile: (Amazing how many non-answers I get on these silly forums)

The average answer seems to be "tunneling diode" but it is difficult to see how one could demonstrate tunneling with such a device - other than to point at it and say "there's tunnelin' in that thar device!" ;)

Thank you very much for both of your replies. I have seen the "photon tunneling on your kitchen table". Someone else is doing that. Yes, we have access to a semiconductor fabrication lab! Just tell me what you have in mind and I can get it rolling!

Hi Y'all, I would like to demonstrate electron tunneling in my Modern Physics lab class. Does anyone know of how to set such an experiment up? We have a lot of equipment and \$ available, so that's not a problem. I don't want to ask the prof beforehand because he's kinda dumb.
13. ### Need mental picture

Well I am just learning this stuff and it's pretty clear that there is a lot of obfuscation going on. So I am taking very small bites. I can definitely visualize a linear transformation. Maps a vector to another vector. Period.
14. ### Need mental picture

Hmm. I take it you've never read David Hume. Anyways, I thought a little about this on my lunch break. I came up with "a linear combination of linear combinations". Doesn't seem like a concept worth worrying about.
15. ### Need mental picture

Hello Gals, I know what a scalar is. I know what a vector is. I know what a linear transformation is. But what in the name of sweet aunt petunia is a rank 3 tensor? Love, Plx Mny

I am interested in learning about spintronics. Anybody around who is familiar this field?
17. ### Top ten physics journals

I didn't know that! Thanks, ZZ. I really didn't think I would get a serious answer in the General Discussion forum. You singled out PRL. But what about PR(A-Z)?
18. ### Appropriate Forum?

Please don't take offense, but I respectfully disagree. Gaining publication in a scholarly journal is very important to a physicist, and if one is rejected by Physical Review, what is the next best choice? I know that there are some journals that will publish crack-pottery, and others that...
19. ### Appropriate Forum?

I tried the academic and career guidance one. I don't really know WHAT is in the general discussion one!
20. ### Top ten physics journals

Gentlemen and Lady, Assuming that Physical Review is the #1 journal to get published in, what would the top 10 be? Love, Plxmny
21. ### Appropriate Forum?

Gentlemen, What is the appropriate forum for the following question: "Assuming that Physical Review is the #1 journal to get published in, what would the top 10 be? Love, Plxmny"
22. ### Question for the experts

Ok I will go with both (Aschcroft and Mermin) and Kittel 7th edition. Thanks, dudes
23. ### Imaginary Action

I think that you are correct. I also heard that landau lifschitz nrqm has an exposition of the technique. i am trying to get a copy now to check. Also I just learned that the cited reference was re-published in 2000 so I might have some luck there. I will let you all know. kisses, plxmny
24. ### Imaginary Action

Thank you - I checked the local university library but they don't have back to 1967 without jumping through hoops. I'll try another tomorrow. In the meantime I hope someone can shed some light on this imaginary action technique for me. I tried posting the same query to crackpot-land (google)...
25. ### Fundimental frequency of subatomic particles.

No - \nu is frequency. You said the object was at rest so there is no velocity.
26. ### Fundimental frequency of subatomic particles.

It's not a loaded question at all! E = h \nu = m\sub_0 c^2
27. ### Imaginary Action

Friends, I am reading that the standard way to discuss tunneling is via imaginary action. The reference cited is J.S. Langer, Ann. Phys. 1967. (1) What is the full name of Ann. Phys. so I can look up this paper? (2) What textbook can I acquire to learn this technique?
28. ### Question for the experts

Hi Guys, I use this forum when I want to speak directly to the experts and not mess with the rabble. What is the best graduate level solid state book?
29. ### Measuring effects of magnetic field on electrons in a tunneling state

I hope this is what you meant - I was led to tunneling magnetoresistance. But the little description I read said only that spin was assumed conserved during tunneling. What if the receiving ferromagnet was not present, and the electrons just went into some detector. Would the spin up electrons...
30. ### Measuring effects of magnetic field on electrons in a tunneling state

Well, you know that I am interested in how tunneling electrons behave in a magnetic field. At first I thought the Lorentz force would be a good effect to look at, but then I learned a little more and I thought maybe the effect of the magnetic field on spin would be better to study. No, I do...